Problem: Combine the like terms to create an equivalent expression: ${2s+(-4s)}$
Answer: Combine the ${s}$ terms: 2 s + ( − 4 s ) = = ( 2 − 4 ) s − 2 s { \begin{eqnarray} 2{s} +(- 4{s}) &=& (2 - 4){s} \\ &=& -2{s} \end{eqnarray}} The simplified expression is $-2s$.